The example you give is a perfect one. We do vet perspective members and particularly vendors. Our Vendor rules are very strict specifically so that we keep the commercial side of HF to a dull roar. That doesn't mean that we aren't bombarded by folks trying to join that are not approved. Many of those are rejected because it is obvious on the surface that they are here to sell. A few make it through and are quickly called-out by members via the Reported Posts. So yes, we do exactly what you're talking about here. Problem is, it is already a lot of work trying to ferret these people out. Adding links and links and links to 'good deals' will only multiply the workload.
But, that's the low hanging fruit. Mods know they will have to work when the accept the job. The real issue is more about focus. We don't want the focus to shift where HF becomes a place to shop. We went through something similar with the whole stove thing. HF is a hammock site, with hammock in the name, where we talk about hammocks. HF is a place to learn and as a byproduct, a place to make new friends. There are plug-ins you can add to your browser to find good deals. There are an infinite number of websites and search engines that provide good deals on just about any topic. There is only one HF. There are a couple of other hammock sites out there, but nobody can claim to be the resource that HF can claim on hammocks. Most of the credit goes to the members, but we attract and keep the members that we do because of the way the site is managed.
I think you will find the mods to be very resistant to commercialization. It contributes very little, as the information is very easy to find, but it adds plenty of problems. It just isn't the path that we want to be on with HF.